Steam generator



April 14, 1931- J. B. SCHEEL 1,800,961

STEAM GENERATOR Filed Jan. 18, 1928 2 Sheets-Sheet l INVENTOR Jo /v 5.50951-2 TTORNEYS,

April 14, 1931. J. B. SCHEEL STEAM GENERATOR 2 Sheets-Sheet 2 Filed Jan.18, 1928 INVENTOR JOHN. B. 5095a TTORNEYS'.

w 70 .0 z J m m Fatente JUHN SGHEEL, U15 JACKSON HEIGHTS, NEW YORK,ASSIGN'OR TO ILA. MONT UORPQ- IIIUFT, 0F WORK, N. 331, A CORPORATION OFNEW YORK ST GENERATUR application filed January 13, 1928. Serial lilo.247,579.

This invention relates to improvements in steam generators and moreespecially genertors of the marine type.

its object is to increase the capacity of tarn'generation in existingunits. An ini ase in eihciency may also result in many es. in theapplication of "Walter Douglas La ll lont, filed August 16, 1927, Serial#213,265, there are disclosed several constructions for protectingportions of a boiler exposed to radiant heat with resultant increase incapacity of the boiler.

In some of the arrangements disclosed in said La Mont application smalltubes operating on the La Mont'principle are inserted in the fire tubesof existing boilers, said tubes extending into the fire box where theyare exposed to-radiant heat. The tubes used, however, in the La Montdisclosure are of hair pin shape which necessitates a rather abruptbend. The present invention seeks, among other things, to provide aconstruc tion in which these abrupt bends are not neoessa-ry, at thesame time providing for ready removability of the generating tubestogether with a construction permitting proper flow of gases through thefurnace while afiording protection to the walls thereof against radiantheat.

in certain marine types of boilers, as, for example, the Scotch marineboiler even in the largest sizes, it is impossible with the,-

present forms of construction to use thefull capacity of the oil burnerdue to the high temperatures generated and, at present, it is found thatabout 500 pounds of oil per hour is all that can be safely burned. Anyamount in excess of this would too quickly burn out the furnace walls,the back of the chamber or the crown sheet or cause leaks in the tubes.The capacity, however, of oil burners in common use is approximately 800pounds of oil per hour and the present invention enables this quantityof oil to be safely burned in furnaces now in use, thus increasing thecapacity from this fact alone.

By the use of the present invention, also, the amount of air which isnow greatly in excess of that necessary for complete combusbox, the viewbeing taken inside the front plate.

Figure 3 is a detail of tributing header.

Figure 4 is a similar view of a discharge header.

Figure 5 is a view, partly in side elevation an intake or disand partlyin section, showing a section of a fire box or furnace with t thereto.

I Figure 6 is a front elevation of a somewhat different arrangement oftubes, diagrammatically shown.

'ligure 7 is a side elevation of Figure 6, an

Figure 8 a rear view of the tubes looking from the line '8-8 of Figure 5in the direction of the arrows.

In the drawings, 1 indicates the supporting structure'of a boiler of akind in general use, although the particular one shown is of the Scotchmarine type. Fire tubes 2 are arranged in three groups or sections abovethe furnace or fire boxes 3, one of these being shown in the enlargedview of Figure 2.

' In Figure 5 the numeral 4 indicates the back wall of the furnace and4a the crown sheet. The gases pass-from the combustion chamber towardsthe back of the furnace,

e invention applied through the fire tubes 2, to theflue 5, thedirection of flow being indicated by arrows. Each furnace opening isclosed by a suitable door or plate shown conventionally at 6, se-

an arm 9 hinged at 10 to the main boiler structure, Figure 1.

The above are the conventional elements of a. Scotch marine boiler. Insuch a boiler burn the oil at a more rapid rate and, therefore, at ahigher temperature-if this could be done with safety. The presentinvention, as already pointed out, has for its objects, among otherthings, to provide for this increased capacity without the usualconsequent danger of injury to the furnace walls.

For this purpose, steam generating tubes are placed in the fire boxor'furnace, said tubes being designated by the numeral 11. As shown inFigure 1, these tubes are connected at the front end of the furnace toan intake or distributing header 12, the tubes extending along thefurnace wall to the rear and back again to a discharge header 13, alsosituated at the front of the furnace. Preferably each tube is formedsubstantially in the shape of a U with one of its branches connected toone header and its other branch connected to another header, one branchof the tube extending along one wall of the furnace and the returningbranch along an opposite wall, the tube making a bend at the rear havinga substantial radius.

Several setsof tubes may be used and in the drawings three sets areshown. The headers are displaced about the furnace ope'ning and may beso located as to form substantially a re lar polygon having an evennumber of si es, the opposite sides being parallel. As illustrated, thetubes of each set are located throughout their length in parallel planesand are of the same size and shape. This is particularly desirable froma manufacturing point of view) Preferably the steam generating tubes 11operate upon the La Mont principle as set forth in application SerialNo. 213,265, filed August 16, 1927, above referred to, although theinvention is not restricted to tubes of this character. Since in suchtubes rapid circulation and ample supply of water is essential, a pump14 is provided for supplying this, the water being taken from the lowerpart of the Scotch marine boiler, which is supplied as usual with itsown water feeding means. From the pump the water passes through a screen15, thence tov a pipe 16 from which it is distributed by branch tubes 17to the intake headers 12, as shown in Figure 1. The intake headers areall connected together as are likewise the discharge headers 13 and fromeach of these latter the steam generated, and any excess water, passesto a pipe 18 which delivers it to a conduit 19 connected to the steamspace of the boiler. The various connections are suitably valved asshown, for the purpose of cutting off any set of tubes of one furnacefrom the system for repair purposes or cleaning.

The intake headers are provided with suitable distributing orifices 20,as shown in Figure 3, these being of the usual La Mont type, and serveto properly distribute the water to the generating tubes in properamount according to the disclosure of application Serial #213,265,already referred to, that is, to say, each. tube is supplied with waterin excess of its evaporating capacity, but insufficient to completelyfill its crosssectional area. In the arrangement of tubes shown inFigures 5 and 8, it will be noted that the tubes of one set overlap thetubes of another set towards the rear of the furnace; The tubes. of thevarious sets,'h0wever, are so proportioned that in the overlapping zonethere is sufficient space between the tubes so that the gases mayreadily pass to the flue without undue obstruction since their heat is,of course, utilized for making steam in the Scotch marine boi r duringtheir passage through the fire tubes 2. This space for gas flow isobtained by extending tubes of the different sets different distancesinto the furnace, as shown in Figure 5. V

In some constructions of furnaces to which this invention may beadvantageously applied, it may not be necessary for the tubes to extendacross the rear of the. furnace but it may be suflicient that theyextend along the side walls. The intake and discharge headers for a setof tubes may then be arranged as shown in Figures 6 and 7, and the wordparallel in the claims is to be 'construed as including such anarrangement. A tube 11 will extend from near the top of an intake headerfrom the point 12a towards the rear of the furnace and back along thesame wall tothe discharge header at the point 13a. Similarly, a tubewill extend from the point 12b back into the furnace and forward againalong the same wall to the point 13?; at the lower portion'bf thedischarge header. The tubes may be supported within the furnace bybrackets 21 indicated in Figure 5, and the entire set of tubes may beremoved from the furnace by breaking the connection from the branch pipe17 to the intake headers and from the branch pipe 18 to the dischargeheaders. The plate 6 may then be replaced, the burner swung to positionand the furnace operated in the ordinary wa It is, of course, understoodthat, variations may be resorted to within the scope of the 129invention without de arting from the spirit thereof and various orms andarrangements of tubes may be used and placements made, all within thescope of the appended claims.

What is claimed as new is: l. in combination, a furnace, a set ofparallel steam generating tubes extending from the front of the furnacealong one wall, across the back and alongan opposite wall again to thefront, and a second set of similar tubes displaced in respect of thefirst set of tubes and crossing the first set at the rear of'thefurnace, said set of tubes being so disposed within. the furnace thatthe planes containing both legs of each tube of each set are arranged atan angle to the horizontal.

2., in combination, a furnace, a plurality of sets of parallel tubesbent the form of a U, a pair of headers for each set, one headerconnecting one branch of all the We and the other header connecting theother branch of all the lls, the headers being located about the furnaceopening, the tubes of each set eatending into the furnace, the sets oftubes overlapping each other within the furnace but suificiently spacedapart in the overlapping zone to permit the furnace gases to readilypass to the flue, said sets of tubes being so disposed within thefurnace that the planes containing both legs of each tube of each setare arranged at an angle to the horizontal.

3. In combination, a furnace, a set of steam generating tubes, each tubeformed in the shape of a if, a header connecting one branch of all theUs, a second header connecting the other branch of all the Us, a secondset of similarly arranged tubes and headers displaced in respect of thefirst set of tubes and crossing the first set at the rear of thefurnace, the planes containing both legs of each tube in each set beingdisposed at an angle to the horizontal.

4:. In combination, a furnace, a set of steam generating tubes extendingfrom the front thereof along one wall, across the back and along anopposite wall to the front; a second set of tubes similarly arranged anddisplaced in respect of the first set of tubes and crossing the firstset at the rear of the furnace, all of said tubes making a bend at therear of substantial radius, the planes containing both legs of each tubein each set being disposed at an angle to the horizontal.

5'. In a fuel burning furnace having an opening to receive the fuelburner, a series of shaped steam generating tubes arranged to surroundthe flame and exposed to the radiant heat thereof and connected to waterinlet and steam discharge headers adjacent the burner, means forpositively circulating water through said tubes, and means for causingthe flow of circulatin water to be in quantity less than sufficient to ithe tubes but in quantity greater than the tubes evaporate.

6. In combination, a furnace, a steam generating circuit including acontinuous steam generating element extending from the front of thefurnace along one wall thereof, across the rear and back along theopposite wall,

means included in the circuit for positively supplying water to saidelement, means for causing the flow of the water to be in quantitygreater than the evaporating capacity of the element but insufficient tofill it completely, and means for withdrawing steam and excess waterfrom said element and recirculating the excess water.

7. A steam generator comprising a furnace having walls and a circularopening, an even number of headers located about the opening to formsubstantially a regular polygon having its opposite sides parallel toeach other, and a set of til-shaped steam generating tubes for each pairofparallel headers, the tubes extending along the furnace walls andhaving their ends connected to the headers, the planes containing bothlegs of each tube in each set being disposed at an angle to thehorizontal.

8. A. steam generator comprising a furnace having walls and a circularopening, an even number of headers located about the opening to formsubstantially a regular polygon having its opposite sides parallel toeach other,

and a set of U-shaped steam generating tubes for each pair of parallelheaders, the tubes extending along the furnace walls and having theirends connected to the headers, all the tubes of a given set being of thesame size and shape and located in parallel planes, and the tubes of thedifferent sets extending different distances into the furnace so as toprovide ample space for the flow of the furnace gases between the curvedportions of the tubes, said sets of tubes being so disposed within thefurnace that the planes of the tubes of each set are arranged at anangle to the horizontal,

9. A steam generator comprising walls formingafurnace having an opening,a steam generatmg tube extending along a wall of the furnace and shapedas a U of substantial radius arranged to have its ends adjacent theopening, a pump operating to supply water to one end of said tube, meansfor causing the flow of water to be in quantity greater than theevaporating capacity of the tube, and means for withdrawing the steamand excess water fromthe other end of said tube.

10. A steam generator comprising walls forming a furnace having anopening, a steam generating tube extending along a wall of the urnaceand shaped as a U of substantial radius arrangedto 'have itsendsadjacent the opening, a pump operating to supply water to oneend-"of said tube, means for.

causing the flow of water to be in quantity greater than the evaporatingcapacity of the tube but insuflicient to completely fillits Ill 05cross-sectional area, and means for withdrawing the steam and excesswater from the other end of said tubeiand returning the excess water tothe pump.

11. A steam generator comprising a fur-. nace chamber having an opening,two headers located adjacent to the opening, and a-set of steamgenerating tubes extending into the furnace which are each bent to theshape of a U having a substantial radiusof curvature and extending alonga wall of the furnace, each tube having one end connected to one headerand the other end to the other header, means including a pump topositively deliver water and distribute it to said steam generatingtubes, and means for withdrawing steam from the other end of said tubes.

12. A steam generator comprising a. furnace chamber having an opening,two headers located adjacent to the opening and on opposite sidesthereof, and a set of U-shape'd steam generating tubes located insidethe furnace, each tube extending along one furnace wall, across thefurnace, and back along the opposite wall, and the ends of the tubesbeing connected to the" headers, means including a pump for positivelysupplying water to one of the headers, means associated with said headerfor distributing water to each of the tubes, and means for withdrawingsteam from the other header.

13. In combination, a furnace and a plurality of sets of steamgenerating tubes, each tube extending from the front of the furnacealong a wall across the back and along the opposite wall again to thefront of the furnace, each set being displaced about the furnacerelative to the other set so that the planes containing both legs ofeach tube in each set are disposed at an angle to the horizontal.

14. A steam generator comprising a furnace chamber havin an opening, aset of steam generating tu es havin their ends adjacent the opening andexten g into the furnace along a wall thereof, a header adjacent theopening connected to one end of each of the tubes and a second headeradjacent the opening connected to the other ends of the tubes, means forpositively delivering to one of the headers the water for steamgeneration, means for distributing it to the tubes, and means forcollecting the generated steam from the other header.

Signed at New York, New York, this 16th day of January, 1928.

JOHN B. SCHEEL.

